Cadillac STS-V shift testing, adjustment 1

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Adjustment 1 set: Kept the 1-2 shift at 30 mph, and raised the 2-3 shift to 60 mph across all shift modes.  Raised the absolute fuel cutoff from 6700 rpm to 7000 rpm.  TM adjusted to 25%.

Interestingly, with no change in shift points the 1-2 shift revved to 6600 rpm and hit a new higher calculated hp value.


Previously the 2-3 shift was commanded at 58 but happened at 60 mph.  When I moved the commanded mph up to 60 mph it continued to be commanded at 60 mph.  More testing needed there to understand.

I observe that the car is actually slowing down during shifts, perhaps due to engine braking in sport mode.  I will plan to retest with the transmission in drive, which does not use engine braking, to see if that is advantageous.

Update:  I see a source of delay in the 0-60 time — wheelspin after the 1-2 shift is a problem.

Mph Time
0 0
5 0.56
10 0.95
15 1.31
20 1.66
25 1.98
30 2.17
35 2.45
40 3.03
45 3.08
50 3.14
55 3.19
60 5.03
Too much wheel spin after the 1-2 shift at 3 seconds is causing a false mph indicator for a spike to 55 mph after the shift.
The 40-55 run in the middle is due to spinning tires.


Reinstated TM and retested.  Didn’t go WOT early enough in the retest to avoid the transmission shifting early 1-2 (shift commanded at 23 mph).



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